Let's roll up our sleeves and solve this. We have 635 and we're going to multiply it by 23, essentially adding 635 to itself 23 times.
Step 1: 0 + 635 = 635
Step 2: 635 + 635 = 1270
Step 3: 1270 + 635 = 1905
Step 4: 1905 + 635 = 2540
Step 5: 2540 + 635 = 3175
Step 6: 3175 + 635 = 3810
Step 7: 3810 + 635 = 4445
Step 8: 4445 + 635 = 5080
Step 9: 5080 + 635 = 5715
Step 10: 5715 + 635 = 6350
Step 11: 6350 + 635 = 6985
Step 12: 6985 + 635 = 7620
Step 13: 7620 + 635 = 8255
Step 14: 8255 + 635 = 8890
Step 15: 8890 + 635 = 9525
Step 16: 9525 + 635 = 10160
Step 17: 10160 + 635 = 10795
Step 18: 10795 + 635 = 11430
Step 19: 11430 + 635 = 12065
Step 20: 12065 + 635 = 12700
Step 21: 12700 + 635 = 13335
Step 22: 13335 + 635 = 13970
Step 23: 13970 + 635 = 14605

So, 635*23 = 14605